Trudeau, 50, sat on the edge of his chair as jurors entered the Chicago federal courtroom but showed little emotion as the verdict was read. Earlier Tuesday attorneys delivered final arguments in the case in which Trudeau was accused of violating a judge's 2004 order barring him from making false claims about his best-selling book, "The Weight Loss Cure They Don't Want You to Know About."

But Trudeau lawyer Thomas Kirsch argued prosecutors failed to prove their case, noting they called just two witnesses.

Trudeau could face years in prison.

Trudeau, who lives in Oak Brook, a Chicago suburb, looked on calmly as a government attorney accused him of lying repeatedly in his infomercials, which were ubiquitous on late-night television.

The core dispute revolves around dramatic claims in Trudeau's TV infomercials about the book, including that people who followed the diet could eventually eat anything they wanted without gaining weight.

The book describes a diet of 500 calories a day and the use of prescription hormones. The truth of the claims in the book itself weren't at issue in the trial -- only the claims Trudeau made on TV as he sought to get viewers to purchase the book.

Kirsch argued that prosecutors had fallen short of their burden to prove Trudeau's guilt. Kirsch also said prosecutors had failed to show that any possible misstatements in the infomercial were intentional.

In a related civil case, Trudeau has already been ordered to pay a $37 million judgment. The federal judge in that case said he was not convinced by Trudeau's insistence that he was broke and couldn't pay. Federal officials said they believe Trudeau is hiding money in secret foreign bank accounts.